In terms of how big it is, apparently it is the weight of 10 Boeing 747s, and a 747 would fit inside its dish. It is sensitive enough to detect the signal from a mobile phone on the moon. It was built just over 50 years ago, around the same time as the first Sputnik, whose carrier rocket it detected.

The 'guide also mentions Goonhilly, which is in Cornwall (went before i had a digital cam, so any pictures will be buried in the house somewhere).
BUT Goonhilly is not a "space" dish but one used for picking up satellite signals. I think the first time the olympics was broadcast live in Britain from the USA it came through there, but the satellite was orbiting too low so they needed the world's fastest dish to track it, and also it would dip below the horizon now and then and they'd lose the image... which must have made actually watching it a hit and miss affair